Part 4/12:
Rick describes the song's intro, highlighting the D to A progression that outlines the D major chord. He emphasizes McCartney's use of arpeggios, notably in the verse where the progression moves through A, B7 (a secondary dominant, preparing for resolution), D, and back to A. The B7 chord is particularly interesting because it functions as the five of the five (V/V), adding harmonic interest and anticipation.